This invention relates to fuel injectors for the fuel systems of internal combustion engines.
Fuel injection systems for automotive engines may utilize a plurality of electromagnetic fuel injectors, each of which delivers fuel to an inlet port of an associated engine combustion chamber. The injectors may be mounted in sockets of a fuel rail which supplies fuel to each of the injectors. The injectors deliver fuel to the engine in metered pulses which are timed to control the amount of fuel delivered and to coordinate fuel delivery with engine operation. The sequential operation of the fuel injectors causes pressure pulsations within the fuel rail which can result in fuel line hammer and maldistribution of fuel from the fuel rail during engine operation.
U.S. Pat. No. 5,617,827 discloses a fuel rail for delivering fuel to multiple injectors of an engine through individual cup connectors spaced along the fuel rail. The fuel rail has a pulsation damper assembly mounted within the fuel conduit of the fuel rail. The damper assembly includes an enclosed air space bounded by compliant walls that flex to reduce peak pressure pulsations in the fuel rail during injector operation to minimize fuel line hammer and resultant fuel maldistribution.
The present invention provides engine fuel injectors which incorporate integrated pulsation dampers that act within the injectors to reduce the rate of change of internal fuel pressure due to opening and closing of the injector fuel injection valves. The reduced rate of fuel pressure change slows down the wave speed of the resultant pressure wave and results in a reduction of the amplitude of fuel pressure pulsations transmitted to an associated fuel rail or other fuel system. A number of embodiments of integrated pulsation dampers are disclosed.
These and other features and advantages of the invention will be more fully understood from the following description of certain specific embodiments of the invention taken together with the accompanying drawings.